Attachment of key opener to can ends or like container parts



Nov. 28, 1950 2,532,166

G C. HOOK ATTACHMENT OF KEY OPENER T0 CAN ENDS 0R LIKE CONTAINER PARTSFiled March 11, 1946 Patented Nov. 28, 1950 ATTACHMENT OF KEY OPENER T0CAN ENDS OR LIKE CONTAINER PARTS George CcHock, Chicago, I 1l., assigncrto Continental Can Company, Inc., New York, N. Y., a corporation of NewYork Application March 11, 19.46, SerialNo. 653,568

8 Claims.

1 This invention relates to a can end or like container part withattached key opener and to methods of attaching key openers to can endsor like container parts.

It is common practice to detachably connect a key opener to a can of thekind equipped with a tear strip which may be removed from the can bybeing wound up on the key opener. Usually the opener is welded orsoldered to the cement). and is formed with a reduced section orotherwise weakened portion for facilitating detaching of the key openerfrom the container. The key opener is detached from the can end by.being bent and broken at the weakened portion.

The desirable structure has the opener fitted tightly against the canpart with minimum projection from the surface of the part, whereby toavoid accidental contact and separation; and has an extensive portion ofthe opener free of attachment over the area of such portion, so thatsuch portion may be grasped by the fingers, or pried away by a toolintroduced between the opener and can, in preparation for exerting force,uponthe opener to detach it from the can. That is, the actual adhesionor attachment spot should be of limited but defined area, and located ata predetermined part of the opener.

A disadvantage resulting from soldering or welding a key opener to a canis that the movement of parts and the high temperature employed n allduring attachin particularly when attachment is effected by welding,frequently fractures or otherwise damages the lacquer coatings withwhich many cans are provided. For example,

when a can end has an inside baked lacquer coating for protectionrelative to the intended package contents, this coating may requirerupture before the welding current may flow at the point of contact ofthe openerand can end, so that the intended protection is lost at thesecontact points: and in addition the heat of Welding may Joe conductedthrough the thin metal and cause scorching of this lacquer coating.

When metal-adherent resins such as phenol- .formalclehyde condensatesare employed as fused the rigid mass and cause premature detachment.

When such resins are employed in solution as an adhesive, difficultiesarise inwobtaining; adhesion spots between the opener and the containerpart capable of resisting the usual accidental mechanical strains andyet having a satisfactory low maximum total adhesion in order that the:opener can be easily separated when so desired. Thin resin solutionscannot be applied, on a feasible commercial basis, over limited anddefined areas of thecontacting container part and opener, and then driedby evaporating the solvent, without tensive equipment for holding theparts and t icti-ng the movement of the solution: thus, he. opener isbonded for its entire area, by capillary movement or simple flow, thereremains no part for grasping incident to intended removal; while ifapart of the opener is preserved :fromsuch bonding by being bent out ofposition closely adjacent the can part, it is exposed to accidentalcontact and premature separation and loss.

.Anobj'ect of the invention is to provide an improved method forattaching key openers to containers.

Anotherobject of the invention is to provide a method for attaching keyopeners to container parts, e. g. can ends, in which the attaching isaccomplished by efiecting the adherence to both .the..container part andthe key opener of a substance which is capable of being caused to ad-,heretoa lacquer coating at a temperature lower thanthe temperaturewhich would injure 'the lacquer coating.

Another object of the invention is to provide a method for attaching keyopeners to such con- ,tainer parts by causing a body of non-metallic andelastic substance to adhere to the container part and by causing thenon-metallic substance .toadhere to or to surround a portion of the keyopener.

Another object of the invention is to provide a new article ofmanufacture comprising a container part such as a can end and a keyopener attached to the container part by a simple, inexpensive andimproved connecting means.

Other objectsoi the invention will become ap- -parent from areadin ofthefollowing description, the appended claims, and the accompanyingdrawing.

In the drawings:

Figure 1, isga plan view of a can end and akey opener attached theretoin accordance with the i l ell ion;

Eigure Zisaplan view of a can end as it appears atana intermediate stageof the method, re specifically after applying a; bondingor, adhes racatwt the c an Figure 3 is a view similar to Figure 2 but showing the canend at a subsequent stage of the method, during the application to thecan end of attaching substance to which the key opener is to beconnected, as by being embedded therein;

Figure l a plan View of a key opener to which a bonding coat has beenapplied preparatory to attaching the opener to the can end;

Figure 5 is a plan View of the can end at a still later stage, andshowing the key opener laid in contact with the attaching substance;

Figure 6 is a plan View illustrating the step of embedding the keyopener in the attaching substance;

Figure 'l is a transverse section through the completed connectionbetween the can end and the key opener, the section being taken on theline 2-? of Figure 6;

Figure 3 is a plan view of a modification in which the key opener isattached at its extreme end portion to a can end; and

Figure 9 is a plan view of a modified form of key having a portion ofreduced section adapted to be embedded in material by which it isconnected to a can end.

Methods in accordance with the invention may be used for attaching keyopeners to various container parts. For the purpose of illustration apreferred method of practicing the invention will be described as beingused for attaching a key opener A to a metallic can end B which islacquered or enameled on its inner and outer surfaces i and 2.

Generally stated, in carrying out the method a body 8 is caused toadhere to the surface 2 and a portion of the hey opener A is connectedto or is embedded in the body 3. Thus, the body 3 preferably comprises afirst substance having such characteristics as to be capable of beingcaused to adhere to the lacquer coating on the surface 2 at atemperature lower than the temperature which would fracture or damagethe lacquer coating; and also comprises a second substance ca able ofbeing affixed to the first substance at a l ewise low temperature.

In a preferred way of practicing the method, a small area of the can endsurface 2 first is coated as shown in Figures 2 and 7 to provide a thinbonding film by use of a suitable adhesive solution of plasticizedrubber hydrochloride. A bonding coating or film of similar adhesivematerial is preferably applied also to a portion of the key opener, forexample as a band 5 on a part of the key opener shank as shown inFigures i and '7.

When the adhesive coating or film l on the can end B has reached apredetermined tackiness by evaporation of the solvent, a thin layer 6 ofa potentially elastic composition comprising rubber (natural orartificial) or rubber latex and containing sulfur, fillers,vulcanization accelerators, oxidation inhibitors or other propercompounding ingredients by which the composition may be cured to itsfinal elastically flexible state, is superimposed on the coat or film 4.The key A, with its coat or film 5 also in a suitably tacky state, isthen laid in contact with the layer 6 as shown in Figure 5. Anadditional layer 1 of material, which be like that composing the layer8, is then app-lied over the layer 6 and the film 5 on the key opener asshown in Figure 6, and is pressed down so as to unite therewith and forma band of rubber or the like material and thus constituting the body 3which may be about one thirty-second of an inch to one sixteenth of aninch thick around the opener.

Finally, the material comprising the body 3 is cured by vulcanizing at atemperature lower than the temperature at which the lacquer or enamelcoatings would be damaged. Baking at a temperature of 225 F. for aboutten minutes or at 350 F. for about three minutes is sufficient.

Strips of uncured rubber tire tread stock may be used instead of therubber or rubber latex composition referred to above.

The bringing of the coats or films 4 and 5 to the desired tackycondition may be accelerated by forced evaporation.

In using the method for attaching a key opener A to a can and B as shownin Figune 8, the procedure followed is the same as that described abovewith the exception that the body 3 of attaching material is applied overan extreme end portion of the key opener rather than over anintermediate shank portion.

The shank of the key opener A shown in Figure 9 has a portion 8 ofreduced section of limited length for receiving a film of adhesivecorresponding to the film 5 shown in Figure 4, being formed by crushingthe shank to flatten it and thus afiord space for the upper portion ofthe body 3 without requiring it to extend for its entire thickness abovethe opener.

The article or assembly disclosed herein comprises the metallic can endB having the continuous undamaged lacquer or enamel coating on thesurface 2 to which the key opener is attached. The connectin body 3 hasthe characteristics of an elastically flexible rubber composition and isbonded strongly to the can end or the lacquer coating thereon, wherebthe key opener is firmly connected to the can end so as not to be apt tobecome detached accidentally, but has a limited movement as permitted bythe elastic nature of the attaching composition and hence absorbs blowswhich would be capable of breaking a connection formed by non-yieldingor brittle material. The connecting body 3 also permits elasticallylifting a part of the opener to obtain a grip thereon to break theconnection, when separation is intended.

Figure 1 is. shaded to indicate a lacquer coating on the surface 2 ofthe can end B. Although an additional advantage is obtained when a keyopener is attached to a lacquered container part in the manner describedabove, it will be apparent that the invention may advantageously be madeuse of in attaching key openers to unlacquerecl or to so-called plaincontainer parts. Figure 1 only is shaded to indicate a lacquer coating.

The method and article disclosed by way of example are preferred but itwill be understood that changes may be made without departing from theinvention as defined in the claims.

I claim:

1. An article of manufacture comprising a metallic container part, anopener, and a composite structure elasticall securing said opener tosaid container part; said composite structure comprising a film ofplasticized rubber hydrochloride in adherent relation to the containerpart, and an elastically flexible body of rubber composition adherent tothe said film and having a loop surrounding a part of the opener wherebyto permit elastic movement of the opener relative to the container part.

2. An article of manufacture comprising a container part, an opener, anda composite structure elastically securing said opener to said containerpart; said composite structure comprising films of plasticized rubberhydrochloride in individual adherent relation to the key opener andcontainer part, and a body having a cross-section smaller than the areaof the opener and formed of cured elastically flexible rubbercomposition adherent to both said films whereby to permit elasticmovement of the opener relative to the container part.

3. An article of manufacture comprising a container part, an opener, anda composite structure securing said opener to said container part; saidcomposite structure comprising films of plasticized rubber hydrochloridein individual adherent relation to the opener and container part, and abody having a cross section smaller than the area of the opener andformed of elastically flexible rubber composition adherent to both saidfilms, said body including a loop of the flexible compo sition extendingaround a part of the opener.

4. The method of flexibly and elastically attaching an opener to acontainer part, which comprises applying a bonding film of plasticizedrubber hydrochloride to said part, applying a bod of curablepotentially-elastic rubber composition to said bonding film andimbedding a portion of said opener in said body, and curing the rubbercomposition, said body in cured condition providing a flexible andelastic connection permitting relative elastic movement of the openerrelative to the container part.

5. The method of flexibly and elastically attaching an opener to acontainer part, which comprises applying a bonding film of plasticizedrubber hydrochloride to said part, applying a bonding film ofplasticized rubber hydrochloride to a portion of said opener, and theneffectin connection of said films by an interposed body of rubbercomposition adherent to both said films, said body being upon completionof the connection of elastically flexible behavior, said body in curedcondition providing a flexible and elastic connection permittingrelative elastic movement of the opener relative to the container part.

6. The method of flexibly and elastically attaching an opener to acontainer part, which comprises applying a bonding film of plasticizedrubber hydrochloride solution to the said Part, evaporating the solventtherefrom until the bonding film is tacky, effecting adherence to thetacky bonding film of a mass of curable potentiallyelastic rubbercomposition, the opener having a part of its structure surrounded bysaid mass, and then curing the rubber composition while detaining thekey opener in such surrounded condition, said body in cured conditionproviding a flexible and elastic connection permitting relative elasticmovement of the opener relative to the container part.

7. In a method of flexibly and elastically attaching a key opener to acontainer part, the steps of applying a bonding coat to said part,effecting adherence of a first layer of curable potentially-elasticsubstance comprisin rubber to said coat, applying a bonding coat to aportion of said key opener in contact with said layer of substance,placing an additional layer of said substance over the bonding coatedportion of said key opener and in adherent contact with said firstlayer, and treating said layers to cure them as a single bod of elasticmaterial bonded to said container part and in which said bonding coatedportion of said key opener is embedded with permissive elastic movementrelative to said container part.

8. In a method of flexibly and elastically attaching a key opener to ametallic container part which is coated with lacquer susceptible tobeing damaged by application of heat at a temperature substantiallyabove 350 degrees: F., the steps of efiecting adherence of films ofplasticized rubber hydrochloride to the lacquer coating and to said keyopener, placing a body of curable potentially-elastic rubber compositionin adherent contact with both said films, and curing said body by theapplication of heat at a temperature not substantially above 350 degreesF., and thereby causing said body to become a flexible and elasticconnection between the key opener and the container part for permittingelastic relative movement thereof.

GEORGE C. HOOK.

REFERENCES QITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 305,680 Drake Sept. 23, 18842,003,494 Reynolds June 4, 1935 2,047,250 Bardet July 14, 1936 2,246,795Daniels June 24, 1941 2,304,718 Swart Dec. 8, 1942

